Hi Everyone. I am restoring a 1970's vintage automotive tune up machine and require some technical information regarding a component. It is marked ITT TS1201 72F . I think it may be a thyristor but I'm not sure. I contacted ITT but they were unable to assist. I think it may be an OEM special build which is why it is not shown in any publications. I would like to identify any possible way replacement for it. All assistance would be greatly appreciated. Thanks.